Tape cable connector



Oct. 26, 1965 H. P. DUPRE ETAL. 3,214,723

TAPE CABLE CONNECTOR Filed June 5, 1961 BY/ MKZ United States Patent O3,214,723 TAPE CABLE CONNECTOR Henry P. Dupre, Wilton, Hans `Graichenand Robert G. Knowles, Norwalk, and Rocco J. Noschese, Rowayton, Conn.,and Eugene Oshva, Long Island City, N.Y., assignors to BurndyCorporation, a corporation of New York Filed June 5, 1961, Ser. No.114,984 1 Claim. (Cl. 339-99) This invention relates to electricalconnectors, and more particularly to connectors for flat flexible cable.

A tape or printed cable is essentially a plurality of flat or ribbonlike conductors disposed adjacent each other in a common plane andsupported by a dielectric. The tapes are manufactured in divers ways;e.g., conductor strips may be disposed between two dielectric sheets andthe sheets bonded together; or metal foil may be cemented to adielectric sheet, the foil milled into strips, and a second dielectricsheet cemented over the foil. Many of these tapes are made of copperribbons sandwiched between two layers of dielectric such as variousforms of polyesters, uorinated polyethylene plastics, polyvinyls, orsilicone rubber.

A major problem in the use of flat flexible cables is their connectionto electrical equipment or to other flat flexible cables. The conductorsare thin, closely spaced, and insulated. The conductors may have asurface lacquer or oxide coat even though they are covered by thedielectric layers, or they may oxidize when the dielectric is removed toprepare a connection. Various methods of attaching connectors to thecables have been proposed. The insulation may be stripped andmulticontact connectors soldered or clamped to the cable. Unfortunately,stripping weakens the end of the cable and exposes the conductors todamage; stripping, due to the thinness of the conductors, may `actuallynick or cut the conductors;

soldering is inconvenient to accomplish and diflicult to qualitycontrol; and clamping is subject to creep.

It is, therefore, an object of this invention to provide a connectorhaving a plurality of contact elements, each of which will make a securemechanical and electrical connection with a conductor in a flat flexiblecable.

It is another object to provide such a connector which may be readilyconnected to and disconnected from a tape cable.

It is yet another object to provide such a connector which requires nopreliminary treatment, such as stripping, of a tlat flexible cable.

A feature of this invention is a connector having a plurality of spacedapart, toothed contacts, each said contact having a plurality of teeth,which are in eifect teeth of uniformly varying length, and which areadapted to penetrate into the tape cable to varying depths and to scrapethe included contact, removing any surface coating, and to ake amechanical and electrical connection therewith.

nese and other objects and features of this invention will"`become moreapparent by reference to the following description taken in conjunctionwith the accompanying drawings, in which:

FIG. 1 is a perspective View of a flat flexible cable to fiat flexiblecable connection utilizing two identical connectors according to a firstembodiment of this invention;

FIG. 2 is an exploded perspective view of the connector of FIG. 1,partially broken away;

FIG. 3 is a detail of FIG. 2 taken along lines 3-3 showing thehermaphrodite contact mating of two connectors according to FIG. 1;

FIG. 4 is a detail of FIG. 2 showing means to align the fiat flexiblecable with the connector;

FIG. 5 is a detail of a contact tooth constructed in acice cordance withthe invention showing the scraping of the contact teeth into the flatflexible cable.

As may be seen in FIGS. 1, 2, 3 and 4, one embodiment of this inventionutilizes a pair of contact blocks which are linked together to obtain acontrolled, scraping, penetration ofthe flat flexible cable.

The -connector assembly 9 shown in FIG. 2 comprises an upper contact`block 11 and a lower contact block 13, carrying a plurality ofspaced-apart, toothed contacts 15 and 17, respectively. The upper andlower contacts 15 and 17, respectively, are in staggered relation toeach other, and the pair of blocks combined have a slight external taperor wedge-shape. The upper and lower contact blocks 11 and 13 areinterlocked by a key 19 and keyway 21 to slide towards each other whilemaintaining their adjacent inner faces 23 and 25 parallel to each other.The upper and lower contact blocks are adapted to be slid into a housingor shell 27 having an inner cavity 29 which symmetrically tapers inheight from a larger height at its front, block-receiving opening 31, toa smaller height at its rear, tape-cable-receiving slit 33. The taper ofthe housing cavity 29 is similar to the external taper of the pair ofcontact blocks 11 and 13.

It will be seen that when the two interlocked, but slightlyspaced-apart, contact blocks 11 and 13 are inserted into the housing,the mating tapers of the housing cavity and the blocks will cam the twoblocks towards each other, while the key 19 and keyway 21 will constrainthe blocks to maintain their inner faces 23 and 25 in parallelrelationship and will also cause a slight relative longitudinal movementbetween the blocks. Thus, when a at ilexible cable 35 having a pluralityof spaced apart conductors 37 disposed within a dielectric 39 is passedthrough the cable-receiving slit 33 and between the contact blocks, 11and 13, and the pair of contact blocks are inserted fully into thehousing cavity 29, the pair of blocks will be brought together againstthe at exible cable 35 with a slight relative movement between theblocks.

Each of the contacts 15 and 17 has a plurality of teeth yformed 41 and43, respectively, therein. These teeth vary .uniformly in size, beingshortest at their rear, or housing cable slit 33 proximate end, andlongest at their front or housing block receiving opening 31 end. Thestaggered spacing between the contacts is equal to the spacing betweenthe conductors 37 of the flat flexible cable 35. Thus, for example, theleftmost lower contact is adapted to engage the leftmost tape-cableconductor; the leftmost upper contact is adapted to engage the secondfrom left conductor; and the second -from left lower contact is adaptedto engage the third from left conductor. The toothed portions of thelower contacts are also spaced longitudinally from the toothed portionsof the upper contacts. This transverse staggering and longitudinalspacingof adjacent upper and lower contact tooth portions provides amaximum air space distance therebetween, to avoid electrical creep orarcing therebetween. The use of teeth of varying length ensures thateaoh tooth will penetrate the tape cable to a slightly different depth.Several teeth will always penetrate the cable insulation to theconductor. Since the depth of tooth penetration becomes progressivelydeeper towards the front end of the cable, if a tooth does pierce theconductor, even severing it, it will not affect the connection since therearward teeth have made a proper connection towards the rear of thetlat flexible cable. If desired, the contacts may be made narrower thanthe conductor, to ensure that piercing 'by a tooth will not sever theconductor. The slight relative longitudinal movement of the contact.blocks ensures that the teeth will scrape the conductors as they passthrough the insulation, ensuring a good electrical connection therewith.Individual teeth at 41 and 43 may have the general configuration of atooth 117 and penetrate a cable 35, as shown in FIGURE 5.

rThe contacts 15 and 17 project out of the contact blocks 11 and 13 andmay terminate in any desired configuration for connection to theassociated electrical equipment or another connector, The contacts are`here shown to terminate in hermaphrodite ta=bs 45 and 47, respectively,which may be spring-tempered and slightly bowed to engage the matingtabs 51, in a mating connector 53, as shown in FIG. 3.

A gasket 55 may be provided adjacent the cable entry slit 33 between theinside rear end of the housing 27 and the rear ends of t-he contact'blocks 11 and 13 to seal the rear end of the housing. A contact sealinggasket 57 and a pressure plate 59 may be provided with openings 61 and63, respectively, to pass the contact tabs 45 and 47 and to seal thefront end of the housing 27. I ack screws 65 may .be used between thepressure plate 59 and the housing 27 to force the contact blocks 11 and13 into the housing cavity 29 to ensure the sealing of the assembly.

If desired, to ensure accurate alignment between the contacts 15, 17 andt-he tape cable conductors 37, pins 67 and 69 may be provided in onecontact block 13 to engage locator holes 71 and 73, respectively,punched into the flat flexible cable 35 as shown in FIG. 4.

FIGURE 5 illustrates the manner in which a contact toot-h such as 117 isapplied to the surface of a cable 35 at an angle, tending to scrape awaythe insulation 39 and any coating on the conductor 37, as i-t is driveninto the cable.

The individual tooth portions of the contact elements shown in theembodiments illustrated in FIGURES 1 through 4 herein, may each employthe configuration and conductor approach angle of tooth 117, shown inFIG- URE 5. Tooth 117 may be seen to be specifically adapted topenetrate a cable at an angle to the cable surface at the point ofcontact, so that a slight scraping motion of the teeth parallel to thecable is achieved.

The invention has th-us been described but it is desired to beunderstood that it is not conned to the particular forms or usages shownand described. The same being merely illustrative, and that theinvention may be carried out in other ways without departing from thespirit of the invention and therefore, the right is broadly claimed toemploy all equivalent instrumentalities coming within the scope of theappendent claim, and by means of which objects of this invention areattained and new results accomplished, as it is obvious that theparticular embodiments herein shown and described are only some of themany that can be employed to obtain these objects and accomplish theseresults.

We claim:

A connector for a cable including a plurality of insulated cond'uctorsdisposed in substantially coplanar, parallel, spaced-apart relationship,comprising:

first and second insulating block members constituting a pair dening amutual interface;

a plurality of spaced-apart contacts mounted in said first block member,each having a plurality of teeth projecting into said interface;

a plurality of spaced-apart contacts mounted in said second blockmem-ber, each having teeth projecting into said interface;

means for moving said block members relative to each other along a pathforming an acute angle with the plane of said interface, said meanscomprising a housing member having an inwardly extending cavity forreceiving said blocks, a key on one of said block members, and a matingkeyway on the other of said block members;

said cavity being of gradually reduced height along the longitudinalaxis thereof for urging said Iblocks toward each other as they arelongitudinally inserted into said cavity; wherein said key and keywayhave their respective mating axes disposed at an acute angle to thelongitudinal axis of said cavity, for producing relative motion betweensaid block members in the longitudinal direction to keep said blockmembers parallel as they are being urged together.

References Cited by the Examiner UNITED STATES PATENTS 2,359,541 10/44Bancroft 339-97 2,929,043 3/60 Phillips 339-99 2,866,170 12/58 Baldridge339-99 3,070,771 `12/62 Piorunneck 339-174 JOSEPH D. SEERS, PrimaryExaminer.

